linux.git/drivers/usb/core, branch v3.18-rc2

usb: hcd: add generic PHY support

2014-09-29T15:54:02+00:00

Add the generic PHY support, analogous to the USB PHY support. Intended it to be
used with the PCI EHCI/OHCI drivers and the xHCI platform driver.

Signed-off-by: Sergei Shtylyov 
Signed-off-by: Yoshihiro Shimoda 
Signed-off-by: Greg Kroah-Hartman

usb: rename phy to usb_phy in HCD

2014-09-29T15:52:59+00:00

The USB PHY member of the HCD structure is renamed to 'usb_phy' and
modifications are done in all drivers accessing it.
This is in preparation to adding the generic PHY support.

Signed-off-by: Antoine Tenart 
[Sergei: added missing 'drivers/usb/misc/lvstest.c' file, resolved rejects,
updated changelog.]
Signed-off-by: Sergei Shtylyov 
Acked-by: Alan Stern 
Acked-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

usb: core: return -ENOTSUPP for all targeted hosts

2014-09-29T15:50:39+00:00

The current code only returns -ENOTSUPP for OTG host, but in fact,
embedded host also needs to returns -ENOTSUPP if the peripheral
is not at TPL.

Signed-off-by: Peter Chen 
Signed-off-by: Greg Kroah-Hartman

usb: core: log higher level message on malformed LANGID descriptor

2014-09-29T01:54:26+00:00

Commit 0cce2eda19923e5e5ccc8b042dec5af87b3ffad0
     USB: fix LANGID=0 regression

defaults to a langid of 0x0409 if it's not properly implemented by the
device. Explain with a higher level error message what this means.

Signed-off-by: Scot Doyle 
Signed-off-by: Greg Kroah-Hartman

usb: Add LED triggers for USB activity

2014-09-25T15:05:12+00:00

With this patch, USB activity can be signaled by blinking a LED. There
are two triggers, one for activity on USB host and one for USB gadget.

Both triggers should work with all host/device controllers. Tested only
with musb.

Performace: I measured performance overheads on ARM Cortex-A8 (TI
AM335x) running on 600 MHz.

Duration of usb_led_activity():
- with no LED attached to the trigger:        2 ± 1 µs
- with one GPIO LED attached to the trigger:  2 ± 1 µs or 8 ± 2 µs (two peaks in histogram)

Duration of functions calling usb_led_activity() (with this patch
applied and no LED attached to the trigger):
- __usb_hcd_giveback_urb():    10 - 25 µs
- usb_gadget_giveback_request(): 2 - 6 µs

Signed-off-by: Michal Sojka 
Acked-by: Felipe Balbi 
Tested-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

usb: hub: allow to process more usb hub events in parallel

2014-09-24T05:33:19+00:00

It seems that only choose_devnum() was not ready to process more hub
events at the same time.

All should be fine if we take bus->usb_address0_mutex there. It will
make sure that more devnums will not be chosen for the given bus and
the related devices at the same time.

Signed-off-by: Petr Mladek 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

usb: hub: rename khubd to hub_wq in documentation and comments

2014-09-24T05:33:19+00:00

USB hub has started to use a workqueue instead of kthread. Let's update
the documentation and comments here and there.

This patch mostly just replaces "khubd" with "hub_wq". There are only few
exceptions where the whole sentence was updated. These more complicated
changes can be found in the following files:

	   Documentation/usb/hotplug.txt
	   drivers/net/usb/usbnet.c
	   drivers/usb/core/hcd.c
	   drivers/usb/host/ohci-hcd.c
	   drivers/usb/host/xhci.c

Signed-off-by: Petr Mladek 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

usb: hub: rename usb_kick_khubd() to usb_kick_hub_wq()

2014-09-24T05:33:19+00:00

USB hub started to use a workqueue instead of kthread. Let's make it clear from
the function names.

Signed-off-by: Petr Mladek 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

usb: hub: convert khubd into workqueue

2014-09-24T05:33:19+00:00

There is no need to have separate kthread for handling USB hub events.
It is more elegant to use the workqueue framework.

The workqueue is allocated as freezable because the original thread was
freezable as well.

Also it is allocated as ordered because the code is not ready for parallel
processing of hub events, see choose_devnum().

struct usb_hub is passed via the work item. Therefore we do not need
hub_event_list.

Also hub_thread() is not longer needed. It would call only hub_event().
The rest of the code did manipulate the kthread and it is handled by the
workqueue framework now.

kick_khubd is renamed to kick_hub_wq() to make the function clear. And the
protection against races is done another way, see below.

hub_event_lock has been removed. It cannot longer be used to protect struct
usb_hub between hub_event() and hub_disconnect(). Instead we need to get
hub->kref already in kick_hub_wq().

The lock is not really needed for the other scenarios as well. queue_work()
returns whether it succeeded. We could revert the needed operations
accordingly. This is enough to avoid duplicity and inconsistencies.

Yes, the removed lock causes that there is not longer such a strong
synchronization between scheduling the work and manipulating
hub->disconnected.

But kick_hub_wq() must never be called together with hub_disconnect()
otherwise even the original code would have failed. Any callers are
responsible for this.

Therefore the only problem is that hub_disconnect() could be called in parallel
with hub_event(). But this was possible even in the past. struct usb_hub is
still guarded by hub->kref and released in hub_events() when needed.

Note that the source file is still full of the obsolete "khubd" strings.
Let's remove them in a follow up patch. This patch already is complex enough.

Thanks a lot Alan Stern  for code review, many useful
tips and guidance. Also thanks to Tejun Heo  for hints how to
allocate the workqueue.

Signed-off-by: Petr Mladek 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

usb: hub: rename hub_events() to hub_event() and handle only one event there

2014-09-24T05:31:12+00:00

We would like to convert khubd kthread to a workqueue. As a result hub_events()
will handle only one event per call.

In fact, we could do this already now because there is another cycle in
hub_thread(). It calls hub_events() until hub_event_list is empty.

This patch renames the function to hub_event(), removes the while cycle, and
renames the goto targets from loop* to out*.

When touching the code, it fixes also formatting of dev_err() and dev_dbg()
calls to make checkpatch.pl happy :-)

Signed-off-by: Petr Mladek 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman